The invention relates to a connector for chains, particularly for tire chains, comprising a substantially C-shaped main body whose free arms define an insertion gap permitting the introduction of chain links and whose yoke portion is provided in a position lying opposite the insertion gap with a stepped bore for receiving a retaining pin which has an annular flange and which in its retaining position prevents accidental detachment of chain links.
In one known connector of this kind (DE-PS No. 765 176), which is intended for tire chains, the retaining pin is provided with an annular flange at each end. The ring flanges form stops preventing the retaining pin, which is mounted in the stepped bore with play, from falling out. In the retaining position one of the annular flanges is situated near the insertion gap, while the other is contained in the stepped bore. In order to hold the retaining pin in the retaining position, the yoke portion and the end face of the annular flange contained in the stepped bore must lie against the tread of the tire. In practice this cannot be achieved, because on the one hand tire chains are not held continuously taut during use, and on the other hand the tread has interruptions resulting from the profile of the tire. The consequence is that the retaining pin may move out of the retaining position and that accidental detachment of the chain links held in the connector cannot be prevented with the necessary certainty. Another disadvantage of the known connector consists in that its yoke part, which has a far greater wearing volume than the webs, faces the tire and not the roadway, which is of course the primary source of wear.
A connector for tire chains which has a yoke part directed towards the roadway or ground is also known (DE-PS No. 1 605 670). In this connector the retaining pin is not received in a stepped bore, but in a plain bore, into which the retaining pin is pressed. If in this second connector it is desired for reasons of strength to use a solid retaining pin, very accurate and consequently cost-intensive machining of the bore is required in order to ensure the necessary press fit. In order to keep the cost of machining low, in practice therefore the expedient has been adopted of using resilient retaining pins; these however have a comparatively small cross-section and under the influence of the external forces acting on them, such as for example impact loads from attached chain links, tend to bend or even to break. Moreover, in both cases, that is to say when either solid or non-solid retaining pins are used, limits are imposed on the forces that can be applied in the fitting of the retaining pins. It is therefore impossible to exclude the possibility that under unfavourable conditions the portion of a retaining pin which projects from the yoke part will be subjected to the action of external forces which exceed the fitting forces and consequently result in the displacement of the retaining pin to a position in which it can no longer fulfil its securing function. This danger increases with increasing wear of the yoke part, since this wear automatically leads to a reduction of the length of the press fit, and thus to a decreased holding force.
The problem underlying the invention is that of providing a connector of the kind first described above, in the production of which high standards of accuracy do not have to be met and which nevertheless in use prevents accidental displacements of the retaining pin throughout the entire life of the chain, even under the most unfavourable conditions.